Cable sheath cutting knife



May 25, 1948. D. D. STONE 2,442,063

CABLE SHEATH CUTTING KNIFE Filed Feb. 28, 1946 2 Sheets-Sheet l Mayv25, 1948. D. D. STONE 2,442,063

CABLE SHEATH CUTTING KNIFE Filed Feb. 28, 1946 2 Sheets-Sheet 2 5 59 M 4%* @ggg- Patented May 25, 1948 UNITED STATES PATENT OFFICE CABLE SHEATH CUTTING KNIFE Dwight D. Stone, Quincy, Mass.

Application February 28, 1946, Serial No. 650,802

18 Claims.

My present invention relates to cutting tools of the blade or knife type, with special but not exclusive reference to longitudinally slitting and transversely cutting the protective armor or sheath of electric conductor cables in preparing them for installation. More particularly the invention aims to provide for such purpose a knife having capacity for precision setting to any necessary depth of cut over an extensive range and whereby, with a known depth of armor for a given cable, the appropriate depth setting may be predeterminedly set selectively and with certainty of precision and accuracy, in making adjustments involving extremely small increments of depth variation. v

These and other objects and advantages will be apparent from the following description in connection with the drawings, in which:

Fig. 1 is a side elevation with parts in vertical section, illustrating one typical embodiment of a cable knife in accordance with the invention;

Fig. 2 is a top plan View of the central toolholding turret and setting means, with the cover cap of Fig. 1 omitted for clarity;

Fig. 3 is a vertical section showing details of the connection and release means at one side of the top plate, that at the right in Fig. 1;

Fig. 4 is a vertical section as on the line 4--4 of Fig. 1, further showing the parts concerned. in Fig. 3;

Fig. 5 is a view mainly in top plan, as looking down on the tool of Fig. 1, but with the turret in horizontal section substantially on the line 5-5 of Fig. l;

Fig. 6 is a side elevation of the tool as a Whole with parts .broken away at the top and with the lower plate and connecting means demounted;

Fig. 7 is a bottom plan view of the lower or bed plate, as viewed from below in Fig. 1;

Fig. 8 shows the cutter blade or knife and its holder bar separately in side elevation, this unit being turned 90 from its position as seen in Fig. 1;

Fig. 9 is a partial sectional view, on a smaller scale, showing certain cable guiding means, the view being in side elevation as if looking from the right on the Figs. 1 and 6; and K Fig. 10 is a bottom plan of the knife head or turret.

Referring to the drawings in more detail, my 'precision cable knife as there shown comprises vopposed supporting elements or plates adjustvably spaced to receive a cable between them. Noting particularly Fig. 1, these include a base `plate or work-supporting bed I and a top plate or table 2. The cutting instrument or knife 3 is mounted on the top plate 2 through the medium .of novel turret-likerpositioning, guiding and indexing means to be described. The work bed I .and the knife 'table 2 are releasably and variably connected by posts 4 and 5 at the opposite sides of the device.

The connector post 4 at the left, see also Figs. 5 and 7, is shown as a screw pivoted at its lower end as at 6 between ears 'I on the bed plate I, so that it may be swung to and from engagement with the top plate 2, the latter slotted as at 8, Fig. 5, to receive it. Desirably a spring 9 at the lower end of the post 4 urges it toward the closed or upright position as in Fig. 1.

Referring particularly to Fig. 1, also Figs. 5 and 6, quick-releasable clamping engagement as between the post 4 and the top plate 2, in any vertically adjusted position of the latter, is provided. For this purpose the threaded portion of the post, which extends substantially its entire length, carries a knurled or other positioning and clamping nut I0 having a collar portion II receivable in the slot 8 of the top plate 2. The underface of the nut Ill is ilat centrally and has a bevelled marginal portion as at I2 for cooperation with a latch Ill spanning the slot 8 and pivoted at one end on the top plate 2 as at I5, Fig. 5. An intermediate portion of the latch I4, Fig. 5, has an inwardly open slot I6 adapted to align with the slot 8 of the top plate 2 so that the latch may be swung horizontally by its projecting ngerpiece I1, to and from enclosing relation to the post 4 and beneath the adjusting nut I0, Fig, 1, as indicated by the full and the dotted line positions in Fig. 5.

As seen in Figs. 5 and 6, inclined cam formations as at I8, I9 at the respective sides ofthe latch slot i6 enable the latch readily to enter beneath the nut I0 (Fig. 1) by engaging the bevelled underporton I2 of the latter and lifting it together -with the post 4 into position for receiving and retaining the latch between it and the up-l per face of the top plate 2. In the closed position as in full line in Figs. 1 and 5, a flat upper face of the latch I4 bordering its slot I6 seats rmly beneath the flat central underface of the nut IIJ.

In Fig. 1, the bed and top plates I and 2 are shown in relatively widely spaced relation, as set up for working on a cable of large diameter, approaching the maximum flor which the particular size of tool is designed. In this connection it will be understood that the invention may be elmbodied in tools of various different sizes and with different overall range of adjustment as may be best suited to a particular eld of service, as for example power transmission cables, as contrasted with leaded telephone cables, or with radio and radar cables, and the various other types and use classications. Approximate maximum, minimum and intermediate cable diameters for which the illustrated knife may be used are indicated by the three broken-line circles at the lower central portion of Fig. 1. Typical cable-diameter capacities for a wide range model such as in Fig. l',

again by way of illustration only. are from say` .300 in. through 2.875 in. diameter.

rEhe Fig. 1 .plate adjustment being as for .a large cable, asj noted, the positioning and clamping nut it accordingly stands adjacent the free upper end of the post t. But whatever the par-Y ticular size adjustment may be, it will be seen and the post.

(Figae and 5) .affording it a' sliding nt on .tifV

connective guide post 5, for selective positioning along it. Removable` stop means such as a cotterV pin 5a, Figs. 1, 4, and 5, at the free end kof the post .deines an"k upper limit for tliefblolck 3e and prevents unintentional separation of the block slide block 3e is adapted to be positively locked in selected position along the that when once set for a givencablefdiamete'r the movable post Il may then be released and subsequently reengaged, to shift the tool'or' to remove it from one cable or portionthereotand tov` install it on another like cable or =portion, mer ely.

by manipulating the Vlatch I Il.

In this connection means desirably is providedY Vfor releasably locking the clamping nutlll, Fig.

nut i@ has a pin "22"projecting at its upper face While the lock nutr has a cooperative pin or screw 23 at its under'face. VAcoil spring surrounding the skirt 2l 0f the lock nut tends-'to space the two nuts and facilitate adjustment. The pins 22 and 23'being disposed in the same path circumferentially' o f'thenuts provide in effect a Alost-motion connection between the two.

As viewed in' Fig. l, turning the lock nut -26 to'.l

the right (counterclockwise as viewedrfrom above inFig. v1)"will cause pin'23 t0k swingaround un- Vtil itengages Vpin' 22 on the adjusting nut l 0, taking it with it, for adjustment of the deviceto accommodate a' larger cable. VFor adjustment to a smaller cable size, turning the adjusting nutll to the left causes 'pin' 22;'toengagepin23 on the lock nutQto cause it to follow. IThe adjusting nut il) is locked in any position by turning nut 2! to the left.

Atthe other sideofthe tool, Fig. 1, the adjustable connection between, the lower and upper plates l, 2 maybe generallys'irrnilar to that as 'already described. Preferably Vhowever the connector elementv is fixed relative .to the bed .plate Iv and is associatedfwith the upper'tableZ 'in a manner permitting rapid adjustment ofthe latter toward and from the bed plate l to any desired extent. Accordingly as illustrated the member 5 is formed as a slidepffrectangular cross-section through a. major ,portion of" its length. The lower end of this slide or guidef is rigidly connected tothe corresponding lateral portion ot the bed plate l, as by extension Ythrough an .aperture therein laterally opposite the pivoted clamp post l5, vthe lowerrpreferably rounded end of the guide 5. havinga retaining screw 26and ananchor nut threaded on it as at 2l. The corresponding side portioncf the upper plate or tool table 2 comprises a centrally divided bracket including spaced arms 28,29,V Fig.

5, pivotallyreceiving'betweenthema slider block v 32 received in annular'grooves atY the'respective ends of the pin.

The vslide block Sil-has a vertical apertu-rerd '3b.' A removable pivot ,pint-fl extends through aligned bearing apertures inthe plate arms"28,

guide post 5, herein by a manually releasable and .automatically locking means. Said means as il- .Y

lustrated, noting particularly Figs. 1, 3, 4 and 5;

comprises a spring plunger 35 slid-ably lreceived inV a lateralrecess in the slider block and having a knurled head or othergripping piece :it at its outer end. The plunger 35 is urged inwardly,

toward the guide post 5 as byaspring lbearing between an annular shoulder '38 ald-jacent theY inner end of the plunger and a removable cover plate 3?) on the block 3%. long the outer -ace of the guide post 5 is a series of selective plungerreceiving recesses te inrclosely spaced relation, any one of which is adapted to receive the plung- Ver and thereby positively lock the block 36 in the correspondingselected Y position along the guide post 5 and hence to space the corresponding side portions of the Ylower and'llpper plates relation to the. particu- `Y carries one or more radial projection (l5 receiv- Y able in the locking notch't, to hold the plunger retracted and to ride along the cam {l3- under-the influence cf the plunger spring. By retracting the plunger and slightly turning it to place one of the projections t5 against the cam the plungerV will automatically Vbe caused to move Vin to locking engagment with thenearest recess of the series coming opposite the plunger as the block the guide postV 5; f

kIt will be understood that to installthe'tool in operative relation to ya cable, as for example the relatively large cable for which the device isset up in Fig. l, the bottom-pivoted post 4 is unlatched andswung outrfree of the tool table 2'. By retracting tl'ieplunge-r 35 the slide block 353 together With the table 2 may be freely shifted along the slide post 5 Vto any necessary extent.V In the example .of Fig. 1 theblock '3d is thus moved toward the upper end of the slide post-5 to lan approximate position as estimated t0 vbe correct for the given cable. The plunger is then released with respect to the locking notched, so that its spring in conjunction withthe described cam 43 causes-the plunger to lock into an adjacent hole ofthe series di?. The clamp nut pair It, 2f@ are turned out to an approximately corresponding position alonglthe swingable post 'y 4. With the latch l open, the device asawhole is appliedabout the cable C; the latter entering Vat-the openingv betweenv the out-swungpost and the-table 2. The closingspring 9 automatically swings the vpost 4 into the open slot 8 of the -'said table. y Y

about the sleeve Il of the clamp Ynut l0.V .If itis 'found that some adjustment is neededforthe opposite side ofthe table 2, Vas between it-and the "slide post 5, suchis then readilyeected by manipulation of the plunger; 35. in; themanner Si). and the tool plate 2 YAare adjusted-lengthwise The latch lll is thereuponvclosed u'explained, the latter automatically relooking into an adjacent recess of the series 40. The clamp nut I is then turned down until the tool runs freely but not loosely through the guides, in this instance the Wheels ISU-ISI, Figs. 1, 6, 9, and 10. The lock nut 20 is then turned to locking position. Having thus set up the work-holding parts for operation on the given cable size C, the tool as a whole may be thereafter released and again engaged with respect to the cable merely by opening and closing the latch I4.

From the foregoing it is evident, particularly with reference to Fig. l, that the pair of adjustably spaced plates I and 2 together with the connecting means ll, and associated parts as above described provide in effectv an enclosure or frame adapted to be installed in surrounding relation to a cable. One of the plates, herein the bottom or bed plate I is provided with posif tioning means engageable With the cable, while the opposite plate, herein the upper plate or table 2, is adapted to present the cutting tool or knife 3. The tool holding means, herein in the form of a turret-like head is constructed and arranged for presenting the knife 3 for operative travel lengthwise the cable so as to slit the protective armor or sheath thereof along a line paralleling the cable, or optionally t0 present the knife in a transverse position for cutting the cable armor or sheath circumferentially. Correspondingly, the cable-engaging element of the opposite or bed plate I also is adapted for cooperative engagement with the cable either longitudinally or transversely of the latter.

Accordingly the bed plate I Figs. 1 and '7 is centrally recessed to form a bearing seat for a carrier or disk 55 rotatably positioned therein. This disk is demountably held against vertical displacement as by means of a cover plate 5I of larger diameter than the recess in the bed plate I and seating flatwise against the top face of the latter. This plate is assembled to the carrier disk 50 as by means of a plurality of screws 52 extending up through the disk 5i! and tapped into the plate. Stop washers 53 on the screws and of a size to overlap the underface of the bed plate I hold the carrier disk 55 against upward displacement. The disk has a central through aperture as at 54 for housing the cable engaging roller 55 in and upon this carrying disk. Opposed intermediate portions of the side walls of the roller-housing aperture are formed with bosses 55, 55, see Fig. '7, between which the hub 55a of the roller 55 is received. These bosses are apertured in line to provide bearingsv for the roller shaft 51. Thus the roller 55 is mounted to rotate freely about the horizontal axis of its shaft 51, While the roller-carrying disk or cage 5U is in turn angularly adjustable about a vertical axis so as to present the roller for rotation in a vertical plane either paralleling the cable axis or transverse to it. The roller and its carrier are releasably held in either adjusted position by suitable means herein comprising a ball detent 58 Fig. 1 positioned in a radial recess in the bed plate I and urged inwardly toward the roller carrier as by a coil spring 55 bearing between the ball and bottom of its recess. The peripheral wall of the carrier disk-5l) has generally V-shaped seating recesses 55apositioned to come opposite and receive the ball detent 53, so as to receive and retain the latter against the pressure of the rather stiff spring 55. In the illustrated example, four such ball seats are represented spaced 90", so that a quarter turn of the relier carrier su in either direction win serve to shift the roller` 55 from one to the other of its operating positions and automatically retain it therein. Desirably the roller 55 has centrally about its peripheral surface a relatively soft metal or other insert 55:6 opposite the knife blade 3, to avoid dulling or injuring the latter through carelessness or mishandling.

Referring now more particularly to Figs l, 5 and 6, the tool-holder element or knife head herein comprises a generally cylindrical housing member or turret 6E! having a central bore in which the tool or knife 3 isadjustably held and from which it is projected to variable extents and by accurately predeterminedly selectible increments of any degree of fineness, through the medium of the novel indexing means to be described.

Accordingly the upper plate or table 2 is formed with a central bearing yrecess 2a disposed axially in line with the center of the seat for the roller carrier disk 5i! of the bed plate I. The turret 65 has an annular bearing portion 6I having a snug bearing fit in the aperture 2a -of the table 2, A peripheral flange 62 on the turret above said bearing portion 6| fits on and provides direct bearing support for the turret at the upper face of the table 2. Below the latter the turret has an annular groove 53 `removably receiving a spring retaining ring and end thrust lbearing member 54, The turret 60 is thus demountab-ly but securely held on the table 2 with capacity for angular adjustment about the turret axis. it is releasably held and positively locked in different positions of angular adjustment, to present the knife 3 for operation lengthwise orl transversely of the cable, as by means of a spring-- pressed plunger 65 having a manipulating head E6; see Fig, 5. The plunger is urged inwardlyl by a spring 5T bearing between a shoulder atl the inner portion of the plunger and a plate 68` screwed or otherwise demountably secured at one side face of the table 2, the plunger and its spring being housed in a recess formed in the table for the purpose. The annular bearing portion 6E Fig. l of the turret has a plurality of plungerreceiving sockets Bla Fig. 5 at the several quadrants of the turret, spaced similarly as for the described locking recesses of the roller carrier 55. Thus the turret together with the knife 3 housed therein may be turned in either direction in adjusting the knife as between longitudinal and transverse cutting operations, irrespective of which position it chances to be in at the time such adjustment is desired similarly as previously explained in connection with the cable roller 55.

The direct holding element for the knife 3 Figs. l, 5 and 8 comprises an elongated lead screw or knife-holder bar 10. The inner or lower portion of this knife holder member 'I0 is of rectangular cross-section as atv 'II Figs. 5 and 8 adapting it for accurate guidance and lateral support in the like-shaped rectangular lower portion of the turret bore, as at 60a, Fig. 1. The inner squared end 'II of the lead screw or knifeholder bar lll is vertically slotted as at 'I2 Fig. 5 to receive the tang 3a of the knife 3, Fig. 8. The knife is demountably secured on its holder bar l0 as by'means of a screw 13. Noting Figs. 5 and S, the lower portions of the holder bar at opposite sides of the tang-receiving slot are apertured in line, the aperture at one side of the knife being tapped to receive the threaded end of the screw while the other side iscountersunk to receive the screw head. The knife l it-whenso desired. f

tang: 3a isi apertured'- lin'e1 with 'the recesses,A

for passage of the attaching Vs`crewgrthe latter' adapted to .be turned-up tightlyto :ciampi-and firmly anchor the knife with'frespee't ft'oithe cooperative lil:e-threadedy adjusting nu-t member 8&1 to be described andwwhichlen'gages the-:bar thread 'l5 willi cause-descending'. adjustmeni'-r of gee-e which 'itl has endwfise -seatinfg engagement. AslY therknife, and.: correspondingly"counter-clockwise turning of the nut will lift thev knife.

ILongitudinal, adjustment ofthe knit-ei '3' Ttoward and from the cable' position s'cias precisely to determine the depthof slice or cut of sheath, is.l herein effected' by means.- ofv a longitudinally Xe-d', rotary adjusting and settingf nut Bil-gr having threaded lengagement withrthe knife: bar 10. Noting Figs. 1 andl .6, this adjusting member 30 is.v centrally disposed1V in and Irotativi-zllyV sup'- ported .at the upper portion of the turret 60, where it ishe'ld against movement in thea'xialfdirection. This nut 8i! comprises ani elongated sleeve-like memberr 8l including a tubular lower portion having intermediate its endsl a downl-Y facing. annular shoulder e2; and at its' upperlend an enlarged head 83 desirably including Wings 84, 84 at diametrica'lly spacerzlpositions to facilitate accuratesetting of the' knife relative to the' calibrated scaleor dialv element- S'j to bef referred to later, Springs vertically hous'ed inthe head 831 as at 83a thrust between the head and the dialfor lfrictionalv holding purposes,` whereb'y'the' winged adjusting nut 80 and the dial 90v gen@-Y erally will turn as a unit butV enabling independaent turning of the dial-for settingthe Zero' niark Vto' adjust the knife 3` longitudinal-ly'. fIhe ball bearingunit comprises an outerring- 85 received on theturretseat 69g and an inner ring ttedon the lower tubularp'ortion 8l off the"` adjusting nutte. Saidtubularnut portion 81" projects beV` low the bearing andiis there annularly groovedito receive aspring lo'ck-` ringl 81 preventing longi` tudin'al displacement ofthefnut and"v the bearing; A plurality of set screws 88 extending through the wall of the-turret-near itslupperend' engage thev outer ring 85"V ofi the' bearing unit to anchor it in the turret substantially'- asin 1.A Since'- the locklring' 81' prevents upward withdraw-allor theadjusting nut' with respect-toi the: inner b"ea;1'Y ingl ring 86', and the latter vis unitarily' associated withA therouter ring 85 through the ball bearing; the setiscrews' serve to' retai'nlthe entire knife;V adjusting 'assembly in'V operative. position? on the turret ESill Referring. now'to Figs; 1,. 2 and'. (inthe4 graduV Vated dial'or zero-setting;elementwpreviously mentioned, indicated generally at 90, comprises'acir'- cular plate or dial` propere-I vcentrally: apertured for reception-fon the =tubular hub portion 8i; of the adjusting-v nut Stebelow the head-stoff the latterg. and? with capacity/ for turning relativeitd iThe dial proper orplate'il 'is-sor ai diameter greenery senses-at- #nfger than the diameter of the 601 so as to 'project beyond thefturret forirea-cl-y engagementbythe opexators-fV lngers; independently adjustable difal'ele` menten 'includes a, Icentral depending colla-r- S2 of reduced diameter conforming substan-tiallyv toy th or the inner 'bal-1'" bearing ringVV A86 again-'st previously notedv a-'nu-mbefrof snringsf in' the dal plate 9i" stha-thSe-'tw partis fend-lib tgethf. Th 166kL ring 32T already" mentioned holds the n'utand'fdial (9 il? against relative dis-v placement the'upvvard direction;A

Aspreviously stated the maj-or 'long-itu'dina'lj rangement i-s` such that clockwise turningoff thev Y adjusting nut 8i! as1 viewed in Fig. 2, in; the in# stin'ctive right-hand manner'for turning one threaded member dow-n into another will lower they knife' toward the cable; For such a-ctionthe' internal threading of the nutY 835 isy made? lefthanded and the externa'lfjthreading T'E'of theknife barl is likewi'serleft-'hand Hence right-hand turning of the axially immovable' nut forces the k'nie downwardly with respect to theturretfGill' A As best seen inv FigL- 1i, the overall lengthlof the Cutter made or knife -31an-dlitshoiderfbar orlead screwV Tissubstahtially greater t-lia-n the axial or' vertical extent-ofthe turretv 5%'- 'andf off the adjusting'nut 8U, toprovide the desiredrar-ige of adjustment for the knife and a-lso .to accommodate a' locking means whereby the knifeis) se-V curely held in' any selected position of adjustment; subject to"V quick release: SucheV means herein comprises asleeve-iike lnclringl nut Illlinternally left-hand threaded at its lower portion as at lill' for cooperation withthe left-hand-knife bar threading l-5`, and having aknurled lateral flange ormanipulating ngerpi'ec'e lilz'by which it may' readily' be turrie'd'- down against or re'' W leased irointhe top face of the adjustingnut' 83"; tolock or unlock the lat-ter' with respectY to the knife' bar 10'. Directive'markings for the lock nut-sucht as arrows and: associated indicia lock and unlock m'ayjb'e providedi in easily'vie'wable position, as onL the' |G2'; see'F 'ig. 2.

lock nut lilil and in either direction of- I nife-V adjusting rotation o'fi the nut til: As herein showr'isuch' means;` noting particularlylig. 1';

comprises a co'il spring' l 915- surroundi'ng-l the lockl nut l'b'elow its'an'ge lll2fand havingits opposite'Y ends-v anchored respectively.Y to" theheadV 83 off thefadjisting nut and'tf the lock nutr |00 asf by means Vof" pins or screws-4 lili.. It? respectively;

Ther centralf borec at thet upper portion: ofv rthe look nut 'Illgz Fig-1- 1,1, above VtheY manipulating flange m25.a desirably'is somewhat enlarged; the

bottom wail off the enlargement providing-a2 stop top4 face of the iingerpieceY- .9.. shoulder as at |03 for engagement by a stop washer Tl removably held at the upper end of the knife bar as by a screw 18. Thus the knife is afforded o, limiting down stop and the lock nut is prevented from unintended dislodging from the knife bar. A protective cap |08 desirably is removably fitted onto the upper end of the lock nut |00, above its ngerpiece |02 and of a length to accommodate the knife bar within it in the maximum elevation of the knife.

In Fig. 1 the knife 3 is shown in a raised position in which it is substantially fully withdrawn into the housing and guiding channel therefore at the lower portion of the central bore of the turret 60. This position is representative of that for a cable of relatively small diameter such as indicated by the broken line circle C2. The projecting lower end 69 of the turret 60, below the table '2 and the lock ring 64 is formed for seating and holding engagement with the work, in a plurality of different angular positions of the turret with respect to the table 2. In the illustrated example the turret is adapted to straddle the cable so as to present the knife 3 for cutting lengthwise the cable and optionally for cutting the cable transversely.

Accordingly, noting Figs. 1, 9 and 10, the projecting lower end 60 of the turret 60, of a generally cylindrical skirt-like nature centrally around and radially spaced from the knife position, is formed with trough-like inverted-V seating formations 60| and 662 in paired alignment along one diameter of the turret, and at right angles thereto with a corresponding pair of similar opposed formations 603 and 600. These seating formations of each pair are at opposite sides of the central knife position. The inclined downflaring faces of each such formation, in the respective pairs, 60|, 602 and 603, 604, are symmetrically disposed with respect to the Vertical plane containing the knife and the axis of its supporting lead screw l0, and they stand in planes which intersect the plane of said axis along a common line. Thus each pair of cable-receiving formations such as 60|', 602 or 603, 604 is adapted to help position the turret and its knife on a cable by engagement therewith at spaced positions along the cable and at opposite sides of the knife, ahead of and behind the latter and in the same vertical plane with the knife axis. Hence either pair 60|, 602 or 603, 604 of guide formations, whichever is then operatively positioned in the fore and aft line of the tool, for longitudinal or transverse cutting respectively, is adapted to seat the cable vertically opposite the knife. It will be understood that such directional terms as vertical are herein used merely for descriptive purposes, and with reference to an upright position of the tool, such as in Fig. 1. In use the tool may be applied to present the knife in any desired plane radially'of the cable.

With the turret in that position of angular adjustment about its axis as shown in Fig. 1, also Fig. 10. the operative plane of the knife coincides with a longitudinal plane through the cable axis, as appropriate for cutting the cable armor or sheath lengthwise. In such position the seating formations 60| and 602 are active. The other pair of like formations 603, 604 is adapted for similar seating engagement with the cable, but with the operative plane of the knife at right angles to that just above mentioned. That is, with the knife turret 60 turned 90 from the Fig. 1 position, to present the seat pair B03, 6114 in the fore and aft line of the tool, the operating plane of the knife 3 thus is transverse ofthe cable, at substantially right angles to the cable axis. The two knife positions as referred to will be evident from a comparison of Fig. 1 and Fig. 8. In Fig. 8, assuming that the cable is seen in transverse section below the knife 3 similarly as in Fig. 1, the knife is viewed as if the turret had been rotated from the Fig. 1 position. In other words, in Fig. 1 the knife is shown as positioned for longitudinal cutting; if now the turret is given a quarter turn from the Fig. 1 setting the knife would then appear in Fig. 1 positioned as in Fig. 8, for transverse cutting.

As previously described, adjustment of the turret and knife as between longitudinal or transverse cutting positions is effected merely by retracting the locking plunger 65, 66, Fig, 5 and rotating the turret 90 in either direction. On arrival of the turret at the desired new position the plunger automatically engages the corresponding one of the radial sockets 6 la of the turret, thereby locking it in said position.

With reference particularly to Figs. 1 and `10, it will be seen that the described pairs of inverted trough-like cable-seating formations 60|, 602 and 603, 604 of the turret will accommodate cable sizes over a substantial range, such as indicated by the smaller and the intermediate broken-'line circles C2 and C1. For any particular size of cable the bed plate I and its cable-engaging roller 55 are adjusted relative to the turret and its supporting table 2 so that the periphery of the roller is brought into rm engagement against the cable and diametrically opposite the knife 3, in the same vertical plane with the latter in the upright position of the tool as inFig.' 1. This spacing adjustment as between the `roll or bed plate Y| and the tool table 2 is effected in a manner already described with reference to the connector posts A and 5 and associatedparts including the means for rapid sliding of the plunger-equipped blockY 30 to and relooking it in any selected position along post 5, and for corresponding rotativeadjustment and locking of the clamping element l0 along the other and swingable post 4 subject to quick release by the latch I4.

Further in this connection, again noting Fig. 1, it will be apparent that the turret-like mounting for the cable-engaging'roll'SS on its carrier 50 turnable on the bed plate provides for cooperative parallel arrangement of the roller andof the knife, for either direction of cutting, that is,v either lengthwise or crosswise of the cable. Thus the turret elements of the two work and to-ol locating plates and 2 mutually cooperate. in. adapting the tool for plural-directional cutting. In the Fig. 1 position the turret 60 of table 2,is angularly disposed to present the knife 3 with its .blade in an operative plane lengthwisev the cable. ret 50 of the bed plate has been turned to land automatically locked by its spring detent 58 in an angular position presenting the roller 55 with its axis transverse of the cable, for cooperative rotation of the roller in the same plane with that of the knife and `of the cable axis. For transverse cutting both the knife-turret and the'rollturret are turned 90, theroller axis then paralleling the cable and the roller being presented in a position to rotate in a plane transverse of the cable so as to follow rotatively about and against the peripheral surface of the cable while the knife cuts the sheath or protective covering' of the latter transversely.

For larger sizes of cables as for example up to Correspondingly the roller-carrying turdemountably received on indiin'dual studs |40, |41 threaded or otherwise demountably fixed in aligned recesses for the purpose in the correspending lateral portion of the upper plate or table 2, at the opposite sides of the clamp-receiving slot 3 therein.

Referring again to Fig. 1, also Figs. 2 and 6, the construction, arrangement and manner of operation of the precision setting means for the knife will now be apparent from the foregoing description. As positioned in Fig. 1, the knife 3 is at or near maximum elevated or retracted position, in which its cable entering point 3c (Fig. 8) extends but little into the mouth or apex of the inverted trough-like guide formations described. This corresponds to a preliminary positioning of the knife as appropriate for a small cable such as C2 of Fig. 1. For the purposes of explanation, assume now that the tool is toy be employed for longitudinally slitting the outer armor or sheath of such relatively small cable C2. From the manufacturers data or from training and experience the worker determines that for this particular size and type of cable the appropriate cut depth for stripping the outer protective element of the cable is 0.030 in. The tool is installed about the cable, the bed plate and the tool table 2 being adjusted to and locked in a position of relatively close approach to each other, in which the work-supporting roller 55 of the lower plate disk 50 is centrally in contact with the under peripheral portion of cable C2 of Fig. l. The knife adjusting nut 80, being rst released by unlocking turning of the lock nut in the direction of the arrow so marked in Fig. 2, the adjusting nut 80 is now turned in the knife lowering direction (in the natural right-hand or clockwise direction) until the point 3c of the knife 3 just engages the top surface of the cable C2. By reason of the described construction and arrangement of the parts including the anti-friction ball bearing means described, the knife adjustment is afforded such sensitivity that contact of the knife onto the cable is easily felt by the operator. For this purpose the periphery of the graduated disk element 90, Figs. l, 2 and 6, is knurled. By brushing the ends of the fingers along this periphery an exceedingly accurate zero setting may be obtained. This preliminary non-piercing positioning of the knife may also be checked visually by sighting from either side of the knife at the apex of the V-guide formations; Fig. 9. In making this preliminary adjustment the relative position of the graduated dial element 90 is immaterial.

In the selected example, the appropriate cutting depth has been assumed as 0.30 in. Conside`r now particularly Figs. 1, 2 and 6, for setting the knife for such cut depth and in association with the given cable size C2, the graduated dial 90 is now independently turned to bring its zero mark opposite an index or pointer provided for the purpose, the unlocked adjusting nut 80 being at this time manually held against turning as by positioning of a finger against one of the nut wings 84. The dial setting index is seen generally in plan at |50 in Fig. 2 and in front elevation in Fig. 6. It is herein conveniently located at the upper front portion of the turret 60 and comprises an upright pointer |5| opposite or adjacent to the edge of the dial 90 so as to be easily readable against the latter. It is secured to the turret 50 in any convenient manner as by means of a small' arcuate plate |52 having the pointer |5| integrally or otherwise fixed to it, the plate being 14 -removably secured to the outer cylindrical upper Wall portion of the turret as by screws |53, |53.

As best seen in Fig. 2, the dial 90 is accurately calibrated with reference to the -interengaging thread formations of the adjusting nut and the lead screw or holder bar 10 for the knife. Merely by way of example, the lead screw and adjusting nut threading may be of ,la in. diameter and 20 threads to the inch, that being, in an average size of my tool, a convenient threading for aiord-ing the desired sensitivity and precision of knife adjustment through extremely small increments, as for example of the order of 0.001 in. in the illustrated example, giving a range of selective setting for one turn of the dial from Zero to 0.050 in. by available increments of 0.001 in.

The scale a, Fig. 2, concentrically arranged about the upper marginal portion of the dial 90 is represented as graduated into 50 equal increments and the calibration is such that each individual spaced niark of the scale 90a represents precisely 0.001 in. of vertical adjustment fol` the knife 3. Numerical and preferably other indicia are herein associated with the scale 90a. In the example of Fig. 2, the 10s of units are indicated by the numerals 10, 20, 30 and 40, from and around to the zero mark which also represents the total of 50 units. The group of 10 units may be further divided into 5s, as by elongation of each 5th individual unit mark. Since it is frequently necessary in connection with cable installation to work in poorly lighted locations, or in which the particular location ofthe cable hinders Visual reading of the dial, provision is desirably made for setting the dial by touch. For this purpose, besides being knurled for sensitive adjustment, the edge of the dial 90 has distinguishing formations, notches, projections or the like corresponding to the zero mark and preferably at least at 10's of units. As seen in Fig. 2, the dial margin opposite the zero marking has a distinctive modification such as a group of three notches 90, while opposite the 10, 20, 30 and 40 marks the dial has single notches or. other means as at 90', 902, 903 and 904. The zero setting is thus readily identified and also distinguished from the 10s locations by the operators finger feeling against the triple notching 90, the 10s settings also being identifiable by touch.

Returning to our particular example of a selected cut-depth setting oi 0.030 in., the `knife blade has been contacted with the cable, and the dial 9| has been turned, independently. to set the zero thereof opposite the pointer or index |5l, by the medium either of the visual or the sensory means or both. Note that in said independent turning of the dial the knife blade is not moved, but remains at the cable surface. Now the operator has only to turn the adjusting nut 80 and I the dial 9|, as a unit and in the direction of increasing values on the dial scale, to bring the selected depth value of the scale to a position opposite the pointer |5l. This depresses the knife blade 30 units of the scale, in other words 0.030 in. in the illustrative example, for making a cut of that depth. l

The unit turning movement oi the adjusting nut and the dial is effected by manually engaging the nut, conveniently by its wings li- 04, the dial automatically following by reason of the described frictlonal holding relation of the parts as insured by the springs 83a, Fig. l.

In our example the-setting sought is 0.030 in. Hence, to make the above knife-depressing adsecured to one plate and being adapted for attachment to the other plate at variable posit-ions along the posts, at least one of the posts having its secured end pivoted to said rst plate for lateral swinging movement to open and close the frame and having screw clamping and quickreleasable latch means cooperatively engageable with the other plate.

8.- In a cable-stripping knife according to claim 7, the construction wherein the pivoted post has a clamping nut threaded on it, the nut including a collar and a head, said other plate being slotted to receive the collar, and the latch means comprises a lever pivoted for movement in the planefof said other plate and recessed in oppoi sition to the plate slot, whereby the lever is pivotally movable to and from a clamping position between the plate and the nut head in which the lever recess receives the nut collar.

9. In a cable-stripping knife according to claim 7, the construction in which the screw clamping means includes an adjusting nut threaded on the pivoted post to overlie the adjacent plate, a lock nut on said pivoted post beyond the adjusting nut and means causing one nut to follow the other in unlocked turning thereof. I

10. In a cable-stripping knife, a knife carrier plate and an opposite cable-positioning plate, a pair of posts for connecting the plates in adjustable spaced relation, one post pivoted at one end to one plate, said pivoted post having quickreleasing adjustable connections with the other plate, said connections including a clamping nut threaded on the post, a latch lever pivoted on said other plate to swing in the plane thereof to and from clamping position, cooperative oppositely open recesses in the lever and said other plate to receive the portion of the pivoted post adjacently below the nut, and interengageable cam formations on the lever and the clamping nut facilitating entry of the lever beneath the nut and whereby the 1ever in moving to clamplng position 'draws the plates toward each other and into pre-set holding relation to a cable passing between them.

11. In a cable-stripping knife, a positioning frame comprising spaced plates having posts for connecting them in variably spaced relation, the posts having corresponding ends secured to one plate and adapted for attachment to the other plate at variable positions along the posts, one of the posts xedly secured to one plate and having a longitudinal flat face presenting a series of locking recesses, a plunger-carrying block slidably associated with said post and pivotally connected to said other plate, anda spring-pressed plunger housed in the block for selective holding engagement with any recess of said series.

12. In a cable-stripping knife according to claim 11, th'e construction wherein the plunger and block have interengageable cam means assisting movement of the plunger to locking position, and alternatively interengageable means to hold the plunger in retracted unlocking position.

13. In a cable-stripping tool, a cutting blade, a blade-holding head, a positioning frame adapted to surround the cable, said head mounted on the frame with capacity for angular adjustment to present the blade for action lengthwise or transverse of the cable. selectively a cable-engaglng wheel, and a carrier rotatably presenting the wheel opposite the blade, the wheel carrier 18 being rotatably supported on the frame for bodily shifting the wheel to conform its plane of rotation to the direction of blade action.

14. In a cable-stripping tool, a positioning frame adapted to surround the cable, a turretlike knife head angularly movable on the frame, a cable-engaging wheel, a carrier on the frame rotatably presenting the wheel opposite the knife head and itself angularly movable coaxially with the knife head, and manually releasable automatically engaging means for holding the knife head and the wheel carrier in the selected and relatively conformant angular positions with respect to the cable axis.

15. In a cable-stripping tool, a tool positioning frame comprising opposed plates adapted to receive a cable between them, laterally spaced posts for adjustably connecting the plates in cablereceiving position, one post being pivotally connected to one plate for outward opening movement to admit the cable between the plates, and spring means urging said post toward closed engagement with the other plate.

16. In a cable-stripping tool, a positioning frame to surround a cable, said frame including a plate mounting a knife head, a knife centrally carried by the head for cutting into a cable within the frame, said head being angularly adjustable on the plate in the manner of a turret and having an inner portion extending through the plate, said inner head portion having a plurality of pairs of cable-seating formations arranged along different diameters of the head and respectively engageable with the cable in different positions of angular adjustment of the head.

1'7. A cable-stripping tool according to claim 16 and including in combination other cableseating formations on the tool frame in a plane radial of the head for positioning engagement with larger sizes of cable.

18. A cable-stripping tool comprising a cablesurrounding positioning frame, a knife-holding head onlthe frame, an elongated knife element carried by the head with capacity for projection and retraction relative to it to give different depths of cut,ian adjusting member rotatably and non-axially movable on the head, threaded connections between'the adjusting member and the knife element, and a depth value selecting dial rotatable on the head coaxially with the adjusting member and adapted at times to turn as a unit with the latter and at times to be turned independently thereof, and zero to maximum depth-calibrated scale and index means associated with the dial and with the head, whereby the knife element may initially be set to contact the surface of the given cable, the dial may then be turned to a zero setting of the scale and index means, and the adjusting member and dial may thereon be turned as a unit to preselect the appropriate known cut-depth setting of the knife element for said given cable.

DWIGHT D. STONE.

REFERENCES CITED The following references are of record in the lle of this patent:

UNITED STATES PATENTS Number Name Date 1,027,549 Kronert May 28, 1912 2,346,227 Martin Apr. 11, 1944 2,385,368 Montgomery Sept. 25, 1945 

